If a rock had 80 radioactive atoms in it when it was formed and it now has 40 radioactive elements in it, how old is the rock?

According to ohrp, a problem is an “unanticipated problem” when it meets which of the following criteria: unexpected, related or possibly related to the research, suggests that the research does not put the subjects or others at greater riskunexpected, related or possible related to the research, suggests the research puts subjects or others at greater riskunexpected, unrelated to the research but still occurring with a subject, suggests the research puts others at greater riskexpected, related or possible related to the research, suggests the research puts others at greater risk

Which best describes the“brain trust” franklin roosevelt promised to make part of his administration? a group of america’s most successful businessmen, who would fix the economya group of hoover’s economic advisers, who would undo previous damage to the economya group of smart advisers, who would assist roosevelt in guiding the nation forwarda group of military veterans, who would assist roosevelt in putting americans back to work

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